Food products having one substance on the inside and another on the outside are well known. Processes and machines for making such food products in an automatic manner are also well known. For example, in U.S. Pat. 544,962 to Copland, one food substance such as a jam is deposited inside an outer dough. This is done by first advancing a piston to force dough out of an annular opening onto a pan and then advancing a second piston to force jam through a central opening. The feed of the inner jam is stopped and pulled back by withdrawing the second piston while the outer dough continues to be deposited so as to cause it to overlie the inner jam. A severance from the outer dough of the food piece is obtained by lowering the pan and thus break the outer dough away. Augers are used to aid in supplying the jam and dough to the cylinders in which the pistons operate. A similar apparatus is shown in U.S. Pat. No. 1,711,750 to Schappner.
An improved automatic machine for making filled baked goods is described in U.S. Pat. No. 3,196,810 to Roth. In this patent a plurality of dies are fed with a dough. U.S. Pat. No. 3,778,209 teaches an apparatus for forming a food extrusion in which an inner meat food is totally enrobed by an outer moldable food by using a pair of augers below the food hoppers. Augers are particularly useful for the extrusion of foods such as dough to achieve a consistent quality, reliability and high efficiency in high speed manufacture of snacks such as cookies, chocolate layered foods and the like.
Cutting of extruded foods may involve many well known techniques such as wires or knives which, as they cut, may also shape the extruded food piece; see, for example, British Pat. 263,578 and U.S. Pat. 3,530,491 to Rejsa. The latter describes a forming die located on upper and lower surfaces of scissors placed to cut the end of an extruded food so as to simultaneously form and sever a food piece. Knives with rounded cutting edges are described in U.S. Pat. 1,370,027 to Locoratola for bunching a strip of candy before cutting the strip into sections.
In the manufacture of coextruded food substances it is common to require that the outer food substance encapsulates
inner food substance. In U.S. Pat. Nos. or enrobes an inner food substance. In U.S. Pat. Nos. 3,778,209 and 3,249,068 the enrobing action is obtained by controlling the motion of pistons used to feed the coextrusions In U.S. Pat. No. 4,251,201 to Krysiak an enrobed food piece is produced with an apparatus that includes specially sequenced augers used to coextrude an inner and outer food from coaxial dies with the sequence coordinated with an iris shaped cut-off valve that is closely mounted to the discharge ports of the dies. The iris valve cuts the coextrusion just at a time when the feed of both the inner filler and outer coating foods is interrupted and the space in which the valve acts is essentially filled with the outer coating food. This technique appears to depend upon a relatively easy flowability of the outer food substance so as to coat the rear of the inner food while the iris valve is about to close and appears limited in operating speed because the feed of both inner and outer foods must be interrupted for each food piece.